Milan will enter the second leg of their Champions League tie with Barcelona as underdogs, despite their stunning 2-0 victory over the Blaugrana at the San Siro.

The expectation from the vast majority is that Lionel Messi will not be kept quiet as he was in the first leg and that Barcelona will eventually sweep the Rossoneri aside.

A fascinating encounter awaits us and the prospect of an away goal for the Italians would force Barcelona to score four, at least, to take them through.

Many believe that Massimiliano Allegri will have to simply park the bus in order to successfully see the Rossoneri into the quarter-finals, but the Camp Nou has the exact same dimensions as the pitch at the San Siro, even though the pitch will roll a little quicker.

Here are four bold predictions for the second leg. Let me know your thoughts on them and write your own in the comments section below.

Allegri to Drop Constant and Play De Sciglio on the Left

Massimiliano Allegri has a big call to make when he decides which full-backs to select.

So far this season, Kevin Constant has been the most consistent defender for Milan, which would suggest that he is likely to win his place back after missing the Derby della Madonnina through injury.

But Mattia De Sciglio was so impressive against the Nerazzurri playing at left-back—both dominant in the tackle and excellent driving forward.

Constant will have recovered in time to face the Blaugrana, should Allergi want to select the Guinean.

But I feel that De Sciglio's patience when facing being tasked with defending in one-on-one situations, as well as his awareness to track his man across the pitch might make him a better candidate for this specific game.

Constant is an incredible athlete and it is admirable how he has adapted to playing his new position. The former Genoa and Chievo player had previously played as a midfielder before this season with the Rossoneri.

Having limited experience in this role, Constant's positional awareness can expose Milan, which could prove especially costly at the Camp Nou when Milan must remain focused without the ball for in excess of 70 percent of the game, if previous percentage statistics are anything to go by.

Ignazio Abate and De Sciglio are able to match Constant's physicality to an extent—Abate might even exceed him in some areas—but they are both vastly more experienced defenders and that is their primary concern when the second leg arrives.

Allegri, despite an urge to be audacious with his tactics, will have seen the young De Sciglio in the derby last weekend and know that this game is no bigger, so the 20-year-old can be trusted for this occasion.

Vilanova (Roura) Will Finally Give Tello Some Action

It has been a point of contention amongst Barcelona fans of late, not that the team is in any spot of bother, currently sitting 16 points clear at the top of La Liga.

Barcelona's style is rarely compromised for the opposition, but the Blaugrana surely needed to tweak things when Milan stifled them for such a prolonged period in the first leg.

Alexis Sanchez is supposed to be that option to change the patient, passing approach. The Chilean, at his best, can be one of the most lethal one-on-one forwards in Europe, dazzling defenders with his tricks and searing pace.

But the former Udinese star has failed to sparkle for Barça, which might prompt Tito Vilanova, or his assistant Jordi Roura, to opt for Cristian Tello at some point, perhaps if the team still trail deep into the second half.

Tello is probably the most direct player at Vilanova's disposal and simply must be selected if Milan can replicate their incredible performance from the first leg.

Milan to Counter on the Left Where El Shaarawy Will Expose Dani Alves

Milan's best bet to grab a crucial away goal will be to slip passes in behind Barcelona's high defensive line.

To be more precise, the diagonal pass from Montolivo into the path of Stephan El Shaarawy could be the out pass to relieve pressure on their defence.

It happened plenty of times in the first leg, but without much success, as Il Faraone was particularly wasteful when he found space behind Dani Alves.

Alves will certainly be keen to burst forward when Sergio Busquets brings the ball out from the centre-backs, Gerard Pique and Carles Puyol, so if Montolivo, Massimo Ambrosini, et al., can cut off the diagonal pass, they should find El Shaarawy with half a pitch in front of him.

The Rossoneri found the 20-year-old darting towards goal in the first half of the first leg, but El Shaarawy's touch evaded him and the chance disappeared.

Milan need to continue to find El Shaarawy in their hunt for an away goal, as his goal against Inter on Sunday proves that he can be deadly when he is afforded the space to get the ball out of his feet and bear down on goal.

Milan to Reach Quarter-Finals by Two Goals on Aggregate

I expect Milan to finish the job that they started at the San Siro and qualify for the quarter-finals of the Champions League.

Barcelona will not panic, and as such, Milan can hold Barcelona at 0-0 for some time before the Blaugrana start to up the tempo.

With the pace of El Shaarawy and possibly M'Baye Niang—should Allegri dare to be ambitious with his tactic—Milan have the potential to score first and then defend the fort from that point, knowing that they can afford to concede three more goals and still progress.

However, with the adrenaline of scoring in the Camp Nou, I expect Milan to replicate Chelsea's display from last season and avoid defeat in Barcelona.

Massimo Ambrosini has rested up in prospect of replicating his colossus performance in the first leg, rolling back the years and proving what an excellent captain and leader the veteran can still be.

Milan actually possess athletes all over the park who can maintain an intense pressing game in the central areas to squeeze the space that Barcelona like to operate in.

Antonio Nocerino and Sulley Muntari can also offer great work rate, even Christian Zapata can push out from the back with Philippe Mexes dropping into the space that he vacates.

Ignazio Abate and Kevin Constant (although De Sciglio might start the second leg) were excellent in tracking the infield runs from Andrea Iniesta and Pedro, so Milan are equipped to deal with the very best that Barcelona have to offer.

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